The prior art discloses various data processing system in which a processor is employed in the system to assist the main processor in the processing of information. Generally, the coprocessor is a special type of processor that excels in performing a specific data processing task, such as floating point arithmetic, which could be relatively time-consuming on a more general purpose type processor.
In other systems, the coprocessor is treated as an equal, and certain protocols and algorithms are established to control the operation of each processor in a manner to ensure that the various applications that are being run by both processors do not interfere with each other.
The prior art also discloses a number of virtual memory virtual machine data processing systems in which a Virtual Resource Manager establishes a virtual machine that operates to execute particular applications "concurrently," in that the system processor or system resources are shared in a time multiplex fashion among the various virtual machines.
While these prior art arrangements operate satisfactorily, they do not provide a solution to a problem that is often faced by the designer of data processing systems and users, where a new system is introduced with a new operating system for which there are no existing application program. The problem involves providing a translation or migration path to permit a customer to continue to run existing programs on the new system and to add new application programs as they are developed, to either provide new function or enhancements to the old applications.
When the new system is not upward program compatible with the customer's existing system and programs, only two practical options exist if the customer wants to take advantage of the enhancements of the new system. The first option is to run both the systems while converting all of the old programs to the new environment. The second option is to attempt to emulate the old programs on the new machine, which generally results in less than optimum performance on the new system.
The present invention provides the relatively economical and novel method to solve the above-described problem.